(1) Field of the Invention
The present invention generally relates to a voice storage system and, more particularly, to a voice storage system which provides voice message recording and reproducing functions for subscribers in a mobile communications network.
(2) Description of the Related Art
FIG. 1 shows a conventional voice storage system, and FIG. 2 shows a sequence of voice message recording procedures performed by the voice storage system in FIG. 1.
The conventional voice storage system allocates a voice storage module (VM) in which a voice message for a subscriber is recorded, with respect to the subscriber.
Referring to FIGS. 1 and 2, a recording request call from a mobile station (MS) 10 is issued to a base station (BS) 11 the recording request call requesting the voice storage system to record the voice message for the subscriber in a fixed voice storage module (VM) 16 allocated for the subscriber. A signal indicative of the recording connection request from the BS 11 is issued to a mobile local switch (MLS) 12. In response to the signal, the mobile local switch 12 issues an inquiry to a home location register (HLR) 13. By the inquiry, the mobile local switch 12 requests the home location register 13 to send back the location of a master mobile transit switch (M-MTS) 15 connected to the fixed VM 16.
In accordance with the information sent from the home location register (HLR) 13, the mobile local switch 12 is connected to the VM 16 via the master mobile transit switch 15 and a mobile transit switch (MTS) 14 in order to perform a voice message recording function. After the connection of the mobile local switch 12 and the voice storage module 16 is established, a sequence of voice message recording procedures is performed. During the sequence, the voice message from the mobile station 10 is recorded and stored in the voice storage module 16.
In the conventional voice storage system, the voice storage module 16 in which the voice message for the subscriber is recorded is allocated with respect to the subscriber. However, when the voice storage module 16 is in a system-down state, in a congestion state or in a busy condition, the mobile station 10 is not able to have access to the voice storage module 16. Thus, the conventional voice storage system cannot record all the voice messages for the subscriber by the voice message recording function when the voice storage module 16 is in a system-down state, in a congestion state or in a busy condition.
If the quantity of the recorded voice messages reaches the capacity of the storage of the VM 16, it is impossible to record an additional voice message for the same subscriber in the VM 16.